Stoneworking-tool.



, 'PATENTBD APR. 14, 1908. G. 'B. RICHARDS. s ToNEWoRKINQ TooL. APPFIOATION FIILED MAY 29. 1907.

V20. v. F 520101. IMIS 7. 5,

INVEN TUR 0,4% TTUlNElf.

ernaar @FFME CHARLES B. RICHARDS, OF CLEVELAND, OHIO, ASSIGNOR 'lO THE CLEVELAND PNEUMATIC TOOL COMPANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

STONEWORKING-TOOL.

No. cenere.

Speccation of Letters Patent.

Batented April 14, 1908.

application met. nages, 1907. sez-u1 No. 376,304.

Ohio, have invented certain new and useful Im rovernents lin Stoneworking-Tools, of

' Whlch the following is a specification,- the by Ithe drill-bit, in drilling the ho principle of the. invention being herein explained and the best mode in which 1 have contemplated applying that principle, so/as to distinguish it from other inventions.

The annexed drawing and the following description set forth in detail, one mechanical form embodying the invention; such detail construction being but one of various mechanical forms in which the rinciple of the invention may beused. Sai annexed drawing represents an axial section of a pneumatic stone Working tool embodying my invention.

The present embodiment of my improvements herein disclosed is a stone working tool ofthe so-called valveless type, in which the reciprocating plunger which impacts upon .the shank of the Working-tool acts as a distributing valve to control the distribution of the motive uid to reciprocate the plunger.

The particular type of stone working tool herein disclosed is a so-called plug-drill, that is, a stone Working tool in which the impact of the reciprocating plunger is delivered to a stone-drilling bit for the purpose of drilling holes in stone or similar substance to admit of the insertion of wedges for cleavage, lewispins forthe attachment of hoisting devices, or for similar purposes.

A -further improvement disclosed in the present stone working tool resides in the provision of means for conducting a continuous stream or jet of live-air down'through the drill-bit and into the hole in the stone for the purpose of mucking the drilled hole, that 1s, blowing out the dust or debris produced e in the stone.

VThe tool has a barrel, 1, the up er or inner end of which is externally screwt eaded for i 4 .the lattachment of a grasping and manipulathandle, 2, which in the present instanceie illustrated in the form of a spade-handle, al-

`Jthough it may, of course, be of any other desired er convenient 1form. The lower; or

`enters the plunger-chamber,

outer end of the 1carrel has a bore, 3, into the lower or outer part of which a tool-nose, A4, is secured. The axial bore of this tool-nose is polygonal and serves to receive and hold the polygonal shank, 5, of the drill-bit or .other working-tool. At the upper end ofthe bore 3 is formed an annular shoulder or rib,

6, so that a cylindrical chamber is formed between the upper or inner end of the tool=nose or socketand said shoulder. A cylindrical striker, 7, has play within this chamber, and

is formed with a circumferential annular groove, 8, and with a nose or projection, 9, upon its upper end and adapted to be struck by the reciprocating plunger. `The striker is formed with an axial bore, 10, extending from its under side u into the body of the striker and then by a lateral channel, 11, out into the bottom oi' the circumferential annu- ,lar groove. A port, 12', is formed in the side of the striker-chamber so as to register and communicate with the circumferential groove of the striker in whatever `position within its chamber the latter may be, and this-port communicates with a channel, 13, in the wall of the hammer-barrel, which channel extends into and communicates with the live-air inlet, 14, formed in the side of the .barrel a short distance above the middle of the same and at the middle ofthe plunger-chamber within the barrel.

The lower end of the plunger-chamber, abovethe annular rib or shoulder 6, is formed into a large-diameter chamber, 15, having one or moreexhaust-ports, 16, through its wallout into the atmosphere. A smallerdiameter chamber, 17, 1s formed between this exhaust-chamber and the oint in the plunger-chamber at which the ive-air inlet at which point the 'diameter of the plunger-chamber is enlarged to forni a piston-chamber, 18, which extends up to a distance from the upper endy of the plunger-chamber, where it is again enlarged to form a live-ainchamber, 19. A two-diameter or diderential plunger, 20, reciprocates within the plunger-chamber, andis for the greater portion of its length of the diameter of the small-diameter ortion of the same. The upper portion bi t e plunger is formed -u'ith a piston, 21, which iis oi the diameter of and reci rocates Within the piston-chamber 18. Slldts or grooves, 22, are milled or otherwise formed at points in the circumference of the plunger and longitudinally extend from a oint in the small-diam-v eter portion of the p unger a distance below Ithe piston of the same, to a point in the piston near the upper end of the lunger.

he lunger is formed with an axial ore, 23, whic extends from the upper end of the plunger and down for the greater part of the ength of the same, where such bore is intersected by a number of exhaust-ports, 24, radiating from the lowerend of the bore and out through the sides ofthe plunger, so as to connect with the exhaust-chamber in the lower portion of the lunger-chamber when the lunger is at the ower end of its downstro e. The drill-bit is formed with an axial bore, 25, which registers with the axial bore 10 in the striker and extends to the cutting end of the drill so as to conduct live-air to such end or point and into the bottom of the drilled hole so as to blow the debris out 'of the same. 1

In practice, the live-air inlet is connectedby means of a suitable pipe or ni ple to a hose or other flexible connection w lch conveys the motive fluid to the tool,-such motive fluid being in a maority of cases compressed air, while it is evi( ent that steam or other elastic fluid under pressure may be employed. If the lunger is in the position illustratedl inthe awin the live-air will pass upward in the s ace etween the smalldiameter portion o the plunger and the sides of the piston-chamber in the barrel and will passte the u per end of the plungerchamber through t e longitudinal grooves in the lunger, so as 4to drive the piston down.. Ward to deliver its blow u on the striker and through the same upon t e end of the'd1'ill shank. lt will be seen that by havi the liveair supplied to the up erend o the plunger-chamber through t e longitudinal grooves, an anple supply 'of live-air will thus e provided to drive the plunger down and l the hammering power of the stone working tool will be comparatively great for a valveless tool. When the plunger has reached the lower end of itsstroke, the exhaust-ports leading. from the axial bore in the plunger will communicate Withthe exhaust-s ace 15 in the plunger-chamber, as that the ive-air above the pist-on may escfpe through the exhaust-port or ports 1n sai admission of airy above the plunger having been cnt ofi when the u per ends of the longitudinal grooves in t e plun er have passed below the shoulder forme between the uppermost enlargement of the plungercham er, which may he termed the live-air chamber, and the upper end of the pistonchamber 18,- so that the lest portion et the chamber,-the

downward stroke of the plunge-iis accomA plishedby the ex ansion ofthe live-air back of or above thep unger. As soon as the air above the plunger has been exhausted and its pressure( reduced, the constant airres# sure upon thesmall-area lower face o the piston 21 upon the plunger will again raise or force the plunger upward until the longitudinal grooves 1n the same communicate with the live-air chamber in the up er end of the barrel, when the plunger W1 again be driven downward to deliver its blow. f It will thus be seen that the plunger is reciprocated byalternate admission and exhaust of live-air a ainst a large-area face ofthe plunger, and y a constant air-pressure upon a small-area piston-surface upon the plunger.I

striker and through the angular passage Vin the latter into and through the assage in the drill-bit, thus eilecting comp ete muckf 95 ing of the drilled hole by the constant stream or jet of liveair throu hithe drill-bit.

Other modes of app) ying the principle of I.

eemployed for the l mode herein explained. Change may there my invention may fore be made as regards themechanism thus disclosed, provided the rinciples of construction set forth respectivelyin the followingI claims are employed. therefore particularly point out and distinctl claim as my invention 1. n a pneumatic stone working tool, the combination of a' barrel or working-c linder, a plun er reciprocating therein, a too -socket at the lower end of the barrel, a working-tool in said socket havin a longitudinal channel, a 'striker-chamber a ove the socket and at the lower end of the plunger-chamber in the cylinder and having an inlet passage throu h its side and connected to the live-air supp y 2. In a pneumatic stone working tool, 'the 120 combination of a barrel or working-c linder, a plun er reciprocating therein, a too socket at the lower end of the barrel, a working-tool in said socket and formed with an axial channel, a striker-chamber in the lower end of the. 125

barrel between the tool-socket and the lower end of the lunger-chamber in the same andy f formed wit an inlet passage in lts side and connected to the live-air supply of the tool, and a striker. having play Within said striker chamber and formed With a circumferential groove communicating with. the lateral inlet' in the chamber and' having an axial and lateral passage communicating with the axial passage of the tool and the bottom of the.

circumferential groove.

. CHARLES R RICHARDS.

Witnesses WM. SECHER; P. C.- lvIooRE. 

